Question

tìm x biết (x-1)^2=(2x+14)^2

Answer 1

\(\left(x-1\right)^2=\left(2x+14\right)^2\)

\(\Leftrightarrow\left[{}\begin{matrix}x-1=2x+14\\x-1=-\left(2x+14\right)\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}2x-x=-1-14\\x-1=-2x-14\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-15\\x+2x=-14+1\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-15\\3x=-13\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-15\\x=-\dfrac{13}{3}\end{matrix}\right.\)

Vậy: \(S=\left\{-15;-\dfrac{13}{3}\right\}\)